926 research outputs found

    Existence for elastodynamic Griffith fracture with a weak maximal dissipation condition

    Get PDF
    We consider a model of elastodynamics with fracture evolution, based on energy-dissipation balance and a maximal dissipation condition. We prove an existence result in the case of planar elasticity with a free crack path, where the maximal dissipation condition is satisfied among suitably regular competitor cracks

    Elastodynamic Griffith fracture on prescribed crack paths with kinks

    Get PDF
    We prove an existence result for a model of dynamic fracture based on Griffith\u2019s criterion in the case of a prescribed crack path with a kink

    A global method for deterministic and stochastic homogenisation in BV

    Get PDF
    In this paper we study the deterministic and stochastic homogenisation of free-discontinuity functionals under linear growth and coercivity conditions. The main novelty of our deterministic result is that we work under very general assumptions on the integrands which, in particular, are not required to be periodic in the space variable. Combining this result with the pointwise Subadditive Ergodic Theorem by Akcoglu and Krengel, we prove a stochastic homogenisation result, in the case of stationary random integrands. In particular, we characterise the limit integrands in terms of asymptotic cell formulas, as in the classical case of periodic homogenisation

    Comparison of the distribution of non-AIDS Kaposi's sarcoma and non-Hodgkin's lymphoma in Europe

    Get PDF
    To evaluate whether some form of mild immunosuppression may influence the geographical distribution of non-AIDS Kaposi's sarcoma (KS), we correlated incidence rates of KS and non-Hodgkin's lymphoma in individuals aged 60 or more in 18 European countries and Israel. Significant positive correlations emerged but, within highest risk countries (i.e.Italy and Israel), internal correlations were inconsistent. © 1999 Cancer Research Campaig

    Leanness and squamous cell oesophageal cancer

    Get PDF
    Background: Squamous cell oesophageal cancer is one of the few neoplasms inversely related to body mass index (BMI). However, it is not clear whether this is due to cancer-related weight loss or to other correlates of leanness. Patients and methods: 395 incident, histologically confirmed cases of squamous cell oesophageal cancer and 1,066 controls, admitted for acute, non-neoplastic diseases, in Italy and Switzerland. Odds ratios (ORs) were derived from multiple logistic regression, including terms for education, tobacco, alcohol, non-alcohol energy, fruit and vegetable intake Results: The ORs for the lowest vs. the highest quartile of BMI in the year before diagnosis were 2.0 in men, 1.6 in women, and 1.9 (95% confidence interval: 1.3-2.9) in both sexes combined. The association with leanness was stronger in heavy smokers, but was not accounted for by smoking and drinking, nor by differences in diet. Weight change in the decade prior to diagnosis showed no linear association with risk. However, cases were not leaner than controls at age 30 (OR = 0.6 for the lowest BMI quartile) and 50 (OR = 1.1). Conclusions: Leanness appears to be an indicator of squamous cell oesophageal carcinogenesis. However, low BMI in the distant past was unrelated to oesophageal cancer ris

    Leanness as early marker of cancer of the oral cavity and pharynx

    Get PDF
    Summary Background: It is not clear whether the purported association of leanness with cancer of the oral cavity and pharynx was due to cancer-related weight loss or to the influence of factors associated with leanness. Patients and methods: Seven hundred fifty-four incident cases of cancers of the oral cavity and pharynx and 1775 controls, admitted to hospital for acute, non-neoplastic diseases, in Italy and Switzerland. Questionnaire included height, lifetime history of weight and of physical activity, waist and hip measurements, and a validated food-frequency section. Results: Leanness at diagnosis was associated with elevated risk in men (adjusted odds ratio, OR for 5-unit decrease in body-mass index, BMI = 1.9; 95% confidence interval (CI): 1.6-2.2 in men). Male cases were significantly leaner than control subjects at the age of 30 and of 50. Thinner women also had an increased risk, but the inverse association with BMI was non linear. In both sexes, the association with leanness was restricted to smokers and moderate/heavy drinkers, but was not accounted for by drinking and smoking habits, nor by differences in physical activity or dietary habits. Conclusions: Leanness appears to be an early marker of some unknown biological effect of smoking and/or of alcohol abuse, which may contribute to the prediction of cancers of the oral cavity and pharynx. Cessation of smoking and substantial reduction of alcohol intake may improve nutritional status, besides stopping carcinogen exposur

    Understanding Factors Leading to Primary Cesarean Section and Vaginal Birth After Cesarean Delivery in the Friuli-Venezia Giulia Region (North-Eastern Italy), 2005\u20132015

    Get PDF
    Although there is no evidence that elevated rates of cesarean sections (CS) translate into reduced maternal/child perinatal morbidity or mortality, CS have been increasingly overused almost everywhere, both in high and low-income countries. The primary cesarean section (PC S) has become a major driver of the overall CS (OCS) rate, since it carries intrinsic risk of repeat CS (RCS) in future pregnancies. In our study we examined patterns of PCS, pl compared with planned TO LAC anned PCS (PPCS), vaginal birth after 1 previous CS (VBAC-1) and associated factors in Friuli Venezia Giulia (FVG), a region of North-Eastern Italy, collecting data from its 11 maternity centres (coded from A to K) during 2005\u20132015. By fitting three multiple logistic regression models (one for each delivery mode), we calculated the adjusted rates of PCS and PPCS among women without history of CS, whilst the calculation of the VBAC rate was restricted to women with just one previous CS (VBAC-1). Results, expressed as odds ratio (OR) with 95% confidence interval (95%CI), were controlled for the effect of hospital, calendar year as well as several factors related to the clinical and obstetric conditions of the mothers and the newborn, the obstetric history and socio-demographic background. In FVG during 2005\u20132015 there were 24,467 OCS (rate of 24.2%), 19,565 PCS (19.6%), 7,736 PPCS (7.7%) and 2,303 VBAC-1 (28.4%). We found high variability of delivery mode (DM) at hospital level, especially for PCS and PPCS. Breech presentation was the strongest determinant for PCS as well as PPCS. Leaving aside placenta previa/abuptio placenta/ante-partum hemorrhage, further significant factors, more importantly associated with PCS than PPCS were non-reassuring fetal status and obstructed labour, followed by (in order of statistical significance): multiple birth; eclampsia/pre-eclampsia; maternal age 40\u201344 years; placental weight 600-99 g; oligohydramios; pre-delivery LoS 3\u20135 days; maternal age 35\u201339 years; placenta weight 1,000\u20131,500 g; birthweight < 2,000 g; maternal age 65 45 years; pre-delivery LoS 65 6 days; mother\u2019s age 30\u201334 years; low birthweight (2,000\u20132,500 g); polyhydramnions; cord prolaspe; 656 US scas performed during pregnancy and pre-term gestations (33\u201336 weeks). Significant factors for PPCS were (in order of statistical significance): breech presentation; placenta previa/abruptio placenta/ante-partum haemorrhage; multiple birth; pre-delivery LoS 65 3 days; placental weight 65 600 g; maternal age 40\u201344 years; 656 US scans performed in pregnancy; maternal age 65 45 and 35\u201339 years; oligohydramnios; eclampsia/pre-eclampsia; mother\u2019s age 30\u201334 years; birthweight <2,000 g; polyhydramnios and pre-term gestation (33\u201336 weeks). VBAC-1 were more likely with gestation 65 41 weeks, placental weight <500 g and especially labour analgesia. During 2005\u20132015 the overall rate of PCS in FVG (19.6%) was substantially lower than the corresponding figure reported in 2010 for the entire Italy (29%) and still slightly under the most recent national PCS rate for 2017 (22.2%). The VBAC-1 rate on women with history of one previous CS in FVG was 28.4% (25.3% considering VBAC on all women with at least 1 previous CS), roughly three times the Italian national rate of 9% reported for 2017. The discrepancy between the OCS rate at country level (38.1%) and FVG\u2019s (24.2%) is therefore mainly attributable to RCS. Although there was a marginal decrease of PCS and PPCS crudes rates over time in the whole region, accompained by a progressive enhancement of the crude VBAC rate, we found remarkable variability of DM across hospitals. To further contain the number of unnecessary PCS and promote VBAC where appropriate, standardized obstetric protocols should be introduced and enforced at hospital level. Decision-making on PCS should be carefully scrutinized, introducing a diagnostic second opinion for all PCS, particularly for term singleton pregancies with cephalic presentation and in case of obstructed labour as well as non-reassuring fetal status, grey areas potentially affected by subjective clinical assessment. This process of change could be facilitated with education of staff/ patients by opinion leaders and prenatal counseling for women and partners, although clinical audits, financial penalties and rewards to efficient maternity centres could also be considered

    Hepatitis C virus and non-Hodgkin's lymphomas: Meta-analysis of epidemiology data and therapy options.

    Get PDF
    Hepatitis C virus (HCV) is a global health problem affecting a large fraction of the world\u2019s population: This virus is able to determine both hepatic and extrahepatic diseases. Mixed cryoglobulinemia, a B-cell \u201cbenign\u201d lymphoproliferative disorders, represents the most closely related as well as the most investigated HCV-related extrahepatic disorder. Since this virus is able to determine extrahepatic [non-Hodgkin\u2019s lymphoma (NHL)] as well as hepatic malignancies (hepatocellular carcinoma), HCV has been included among human cancer viruses. The most common histological types of HCV-associated NHL are the marginal zone, the lymphoplasmacytic and diffuse large cell lymphomas. The role of the HCV in the pathogenesis of the B-cell lymphoproliferative disorders is confirmed also by the responsiveness of the NHL to antiviral therapy. The purpose of this review is to provide an overview of the recent literature and a meta analysis of the epidemiology data, to explain the role of HCV in the development of NHL\u2019s lymphoma. Furthermore, the possibility to treat these HCV-related NHL with the antiviral therapy or with other therapeutic options, like chemotherapy, is also discussed

    Cigarette tar yield and risk of upper digestive tract cancers: case-control studies from Italy and Switzerland

    Get PDF
    Background: Tobacco smoking is one of the main risk factors for oral, pharyngeal and oesophageal cancers in developed countries. Information on the role of the tar yield of cigarettes in upper digestive tract carcinogenesis is sparse and needs to be updated because the tar yield of cigarettes has steadily decreased over the last few decades. Patients and methods: We analysed two case-control studies, from Italy and Switzerland, conducted between 1992 and 1999, involving 749 cases of oral and pharyngeal cancer and 1770 controls, and 395 cases of squamous-cell oesophageal carcinoma and 1066 matched controls. Odds ratios (ORs) were estimated by unconditional multiple logistic regression models, including terms for age, sex, study centre, education and alcohol consumption. Results: Based on the brand of cigarettes smoked for the longest time, the multivariate ORs for current smokers compared with never smokers were 6.1 for <20 mg and 9.8 for ≥20 mg tar for oral and pharyngeal neoplasms, and 4.8 and 5.4 for oesophageal cancer, respectively. For the cigarette brand smoked in the previous six months, the ORs for ≥10 mg compared with <10 mg were 1.9 for cancer of the oral cavity and pharynx and 1.8 for oesophageal cancer, after allowance for number of cigarettes and duration of smoking. Conclusions: The present study confirms the direct relationship between the tar yield of cigarettes and upper digestive tract neoplasms, and provides innovative information on lower tar cigarettes, which imply reduced risks compared with higher tar ones. However, significant excess risks were observed even in the lower tar category, thus giving unequivocal indications for stopping smoking as a priority for prevention of upper digestive tract neoplasm
    • …
    corecore